Electromagnetic isolation (EMI) for advanced radio frequency (RF) modules is challenging conventional fabrication techniques for production of integrated circuits (ICs), e.g., RFIC's. An integrated circuit may be composed of a plurality of semiconductor devices, such as transistors or the like, which can be produced according to a variety of techniques. To facilitate increased integration and speed of semiconductor devices, a trend of continuously scaling semiconductors (e.g., reducing the size and features of semiconductor devices) has emerged. Reducing the size of a semiconductor and/or semiconductor feature size provides improved speed, performance, density, cost per unit, etc., of resultant integrated circuits. However, as semiconductor devices and device features have become smaller, conventional fabrication techniques are being challenged in their ability to produce modules comprising a plurality of integrated circuits located with high proximity to each other, for example, a high density multi-chip module (MCM). During operation of such a module one or more effects can be encountered which engender deleterious operation of one or more of the integrated circuits comprising the module. Such unwanted effects can include crosstalk between one or more RFIC's, performance degradation of a RFIC owing to RF interference with a clocking component, jamming of one or more components where the RFICs form part of a multi-radio module, etc. Further, for example, where the RFICs form part of an analog-digital system, or a digital-digital system, the high clocking speeds utilized in such digital systems can result in the harmonics of the clock extending higher than a RF signal produced by the digitally operating system which, in an aspect, can cause interference of the RF signal.
Conventional approaches to mitigating such deleterious effects can include incorporation of via-fence enclosures and metal lids into a module construction, whereby the via-fence enclosures and/or the metal lids can act as a localized Faraday shield. However, the via-fence enclosures and/or the metal lids, along with other approaches such as metal cans, clamshells, and gaskets can be bulky and add no value to the module. Further, these approaches can also have their own associated fabrication issues and complexities such as joining of the lids, etc., to the integrated circuit by techniques such as brazing, soldering, welding, sealing, laser tacking, gasketing, etc.
Further, the aforementioned conventional approaches are failing to satisfy isolation requirements which are being requested as the operating conditions of RFICs are being further extended. For example, microshielding to satisfy an isolation requirement of about 150 dB. Accordingly, a premium is continually being placed on shielding that will permit miniaturization in conjunction with high performance, as radars and other electronic systems move toward MCM structures.